1. Field of the Invention
The present invention relates to an image forming apparatus forming an image on a recording medium.
2. Description of the Related Art
In a conventional image forming apparatus, for the sake of high-speed processing and cost reduction, it is well known to perform various processing related to image formation by an integration circuit. Also, it is well known to configure an application specific integrated circuit (hereinafter referred to as “ASIC”) into which a central processing unit (hereinafter referred to as “CPU”) is incorporated. Further, frequently, a power supply is commonly used for the CPU and ASIC so as to reduce the cost. For example, as disclosed in Japanese Patent Application Laid-Open No. 2004-009401, in these cases, a communication line provided between the ASIC and an image processing device (hereinafter, image controller) performs various communications related to image formation.
On the other hand, in an image forming apparatus in recent years, it is well known to provide a power-saving mode other than on printing and standby (hereinafter, normal mode) in order to reduce power consumption. In such an image forming apparatus, when a mode is switched from the power-saving mode to the normal mode, it is determined whether or not transition is made between the power-saving mode or the normal mode, based on information transmitted through the communication line connected to the ASIC and the image controller.
In the conventional configuration, however, even in the power-saving mode, since it is necessary to perform communication between the ASIC and the image controller, the ASIC has to be always maintained in a turn-on-state. This configuration thereby offers a problem of increasing the power consumption for the ASIC even in the power-saving mode.